Astronomers Have Spotted a Monstrous Star Factory Built Around Three Galactic Cores

Astronomers have spotted some pretty amazing (and disturbing) things lurking in the far reaches of the universe, like a huge black hole that's older than light itself. But it's not just physical space that separates us from distant objects—it's time, too. Take COSMOS-AzTEC-1, a galaxy about 12.4 billion light years away from Earth. Because it took the light from AzTEC-1 12.4 billion years to reach us, we're seeing a snapshot of the galaxy from eons ago, near the beginning of the universe itself (which is estimated to be about 13.8 billion years old). What's strange is that AzTEC-1 was already gigantic by that point, and pumping out stars at an alarming rate—but scientists don't know how.

Galaxies with rapid star formation aren't that weird—they're called starburst galaxies, and they usually create their stars near their cores. There's a balancing act going on in most galaxies: the gravity of the galaxy pulls gas inward, and the pressure exerted by the gases push them outward. When gravity wins, stars form from the compressed gas, which eventually collapse into supernovae and push all their gas outward again.

Things don't work that way in AzTEC-1.

Instead of having one galactic core, AzTEC-1 has three of them, along with two dense clouds of gas lurking around its periphery. In addition, the outward pressure of its gas is extremely weak, meaning that the galaxy creates stars at a rate of about 1000 times that of the Milky Way. When it was first discovered, astronomers had a low resolution image of the galaxy, which left a lot of its characteristics shrouded in mystery. Recently, however, a hi-res image of AzTEC-1 was taken, which raised even more questions: instead of being a big mish-mash of gas with no structure, which would explain why there was no equilibrium in the galaxy, AzTEC-1 actually has a nice, rounded disc shape, the kind you'd expect from a well-ordered, stable galaxy.

Right now, astronomers are still puzzling over how the galaxy grew so large and what kept it from just collapsing in on itself, because as it stands, AzTEC-1 shouldn't even exist.